Add workaround for zlib bug. gzungetc not well implemented.

diff --git a/gbfile.c b/gbfile.c
index 7d34cebeb04c219ff1954c7f0b16bcea2d285786..e86c491ecd25773670eb6d85c518035790282331 100644 (file)
--- a/gbfile.c
+++ b/gbfile.c
@@ -70,6 +70,7 @@ gbfopen(const char *filename, const char *mode, const char *module)
        file->line = xstrdup("");
        file->mode = 'r'; // default
        file->binary = (strchr(mode, 'b') != NULL);
+       file->back = -1;
        
        for (m = mode; *m; m++) {
                switch(tolower(*m)) {
@@ -242,8 +243,18 @@ gbfread(void *buf, const gbsize_t size, const gbsize_t members, gbfile *file)
        
        if (file->gzapi) {
 #if !ZLIB_INHIBITED
-               int result;
-               result = gzread(file->handle.gz, buf, size * members) / size;
+               int result = 0;
+               char *target = buf;
+               int count = size * members;
+               
+               if (file->back != -1) {
+                       *target++ = file->back;
+                       count--;
+                       result++;
+                       file->back = -1;
+               }
+               result += gzread(file->handle.gz, target, count);
+               result /= size;
 
                if ((result < 0) || ((gbsize_t)result < members)) {
                        int errnum;
@@ -462,12 +473,17 @@ gbfseek(gbfile *file, gbint32 offset, int whence)
                assert(whence != SEEK_END);
 
 #if !ZLIB_INHIBITED
+               if ((whence == SEEK_CUR) && (file->back != -1)) offset--;
                result = gzseek(file->handle.gz, offset, whence);
+               file->back = -1;
 #else
                result = 1;
 #endif
-               is_fatal(result < 0,
-                       "%s: online compression not yet supported for this format!", file->module);
+               if (result < 0) {
+                       if (strcmp(file->name, "-") == 0)
+                               fatal("%s: This format cannot be used in piped commands!\n", file->module);
+                       fatal("%s: online compression not yet supported for this format!", file->module);
+               }
                return 0;
                
        }
@@ -485,7 +501,12 @@ gbftell(gbfile *file)
 {
        if (file->gzapi) {
 #if !ZLIB_INHIBITED
-               return gztell(file->handle.gz);
+               gbsize_t result = gztell(file->handle.gz);
+               if (file->back != -1) {
+                       file->back = -1;
+                       result--;
+               }
+               return result;
 #else
                fatal(NO_ZLIB);
                return -1;
@@ -505,14 +526,17 @@ gbfeof(gbfile *file)
 {
        if (file->gzapi) {
 #if !ZLIB_INHIBITED
-               int res = gzeof(file->handle.gz);
+               int res;
                
+               if (file->back != -1) return 0;
+
+               res  = gzeof(file->handle.gz);
                if (!res) {
                        signed char test;
                        int len = gzread(file->handle.gz, &test, 1);
                        if (len == 1) {
                                /* No EOF, put the single byte back into stream */
-                               gzungetc(test, file->handle.gz);
+                               file->back = test;
                        }
                        else {
                                /* we are at the end of the file */
@@ -544,7 +568,7 @@ gbfungetc(const int c, gbfile *file)
        int r = -1;
        if (file->gzapi) {
 #if !ZLIB_INHIBITED
-               r = gzungetc(c, file->handle.gz);
+               file->back = -1;
 #else
                fatal(NO_ZLIB);
 #endif

diff --git a/gbfile.h b/gbfile.h
index d2ff098cf6f2c50b1d633b3c1935f0900023fc48..7b1d28a7b68afac6ab57899cc3bb4c97ceec9f60 100644 (file)
--- a/gbfile.h
+++ b/gbfile.h
@@ -44,6 +44,7 @@ typedef struct gbfile_s {
        char   *buff;   /* static growing buffer, primary used by gbprintf */
        int    buffsz;
        char   mode;
+       int    back;
        unsigned char big_endian:1;
        unsigned char binary:1;
        unsigned char gzapi:1;